add browser esm export condition to not even try to load diagnostics channel

Fix: #400

Author: isaacs

.tshy/commonjs.json

@@ -10,7 +10,8 @@
     "../src/**/*.mts",
     "../src/package.json",
     "../src/diagnostics-channel-esm.mts",
-    "../src/diagnostics-channel-node.mts"
+    "../src/diagnostics-channel-node.mts",
+    "../src/diagnostics-channel-browser.mts"
   ],
   "compilerOptions": {
     "outDir": "../.tshy-build/commonjs"

.tshy/esm-browser.json

@@ -0,0 +1,17 @@
+{
+  "extends": "./build.json",
+  "include": [
+    "../src/**/*.ts",
+    "../src/**/*.mts",
+    "../src/**/*.tsx",
+    "../src/**/*.json"
+  ],
+  "exclude": [
+    "../src/package.json",
+    "../src/diagnostics-channel-esm.mts",
+    "../src/diagnostics-channel-node.mts"
+  ],
+  "compilerOptions": {
+    "outDir": "../.tshy-build/esm/browser"
+  }
+}

.tshy/esm-node.json

@@ -8,7 +8,8 @@
   ],
   "exclude": [
     "../src/package.json",
-    "../src/diagnostics-channel-esm.mts"
+    "../src/diagnostics-channel-esm.mts",
+    "../src/diagnostics-channel-browser.mts"
   ],
   "compilerOptions": {
     "outDir": "../.tshy-build/esm/node"

.tshy/esm.json

@@ -8,7 +8,8 @@
   ],
   "exclude": [
     "../src/package.json",
-    "../src/diagnostics-channel-node.mts"
+    "../src/diagnostics-channel-node.mts",
+    "../src/diagnostics-channel-browser.mts"
   ],
   "compilerOptions": {
     "outDir": "../.tshy-build/esm"

package.json

@@ -34,7 +34,8 @@
   "types": "./dist/commonjs/index.d.ts",
   "tshy": {
     "esmDialects": [
-      "node"
+      "node",
+      "browser"
     ],
     "exports": {
       "./raw": "./src/index.ts",
@@ -85,6 +86,10 @@
           "types": "./dist/esm/node/index.d.ts",
           "default": "./dist/esm/node/index.js"
         },
+        "browser": {
+          "types": "./dist/esm/browser/index.d.ts",
+          "default": "./dist/esm/browser/index.js"
+        },
         "types": "./dist/esm/index.d.ts",
         "default": "./dist/esm/index.js"
       },

src/diagnostics-channel-browser.mts

@@ -0,0 +1,11 @@
+// this is used in ESM environments that follow the 'browser' import
+// condition, to avoid even trying to load node:diagnostics_channel
+import {
+  type Channel,
+  type TracingChannel,
+} from 'node:diagnostics_channel'
+export type { TracingChannel, Channel }
+
+const dummy = { hasSubscribers: false }
+export const metrics = dummy as Channel<unknown>
+export const tracing = dummy as TracingChannel<unknown>